Door for silos



A. P. ALGER DOOR FOR SILOS Nov. 28, 1933.

Filed April 18, 1932 Patented Nov. 28, 1933 vUNITED 1,936,568

DOOR FOP. SILOS Arthur P. Alger, ()neida, N. Y.

Application April 18, 1932. Serial No. 605,859

Claims.

My invention relates to a door for silos and I declare the following to be a full, clear, concise and exact description thereof sufiicient to enable anyone skilled in the art to which it appertains 5 to make and use the same, reference being had to the accompanying drawing in which like reference characters refer to like parts throughout the specifications.

The object of the invention is to provide a door for a silo that will be of simple construction and made of a light metallic material, whereby it can be easily manipulated and at the same-time render strength to overcome the greatest possible resistance from the ensilage stored within the silo.

The door is constructed in sections which may be removed separately if found necessary. They can slide vertically, whereby to uncover the space of one section at a given time to allow for removing the ensilage, as it is gradually depleted or lowered in the silo.

One of the difliculties heretofore experienced in the construction of doors for silos was to effect a perfectseal which is necessary for the preservation of the ensilage and yet overcome the handicaps due to the warping or expanding of the wooden door heretofore used. This diificulty is more fully. realized when there is taken into consideration that the joints in the door frame are subject to changes due to the weather as influenced by the different seasons of the year.

Moreover, a wooden door is not desirable for the reason that it is subject to shrinkage when the silo is empty and to swelling when it is filled with ensilage due to the moisture in the ensilage which contacts with the inner surface of the door.

It will be observed, therefore, that if a wooden door is fitted to the door frame with any degree of exactness, when silo is empty and frame dry, it will become set in position when silo is filled with ensilage. Hence the employment oftools to pry the door loose and the consequent wear and tear on door, which wear and tear shortens its life.

The present invention is designed to overcome the difiiculties above mentioned by providing a metal door built in sections which is not subject to warping. Any expansion or contraction of the metal, however, is compensated by arching the door inward or making it in the form of a segment of a circle with the convex surface innermost, whereby to effect a given amount or" spring or yield in each section.

Furthermore, such a metal door supports itself in position by its rolled or folded edges contacting with the wooden, metal or composition surfaces of the door frame having guideways for the vertical sliding motion of said door sections. Moreover, the door sections will be held in any given position by the frictional contact of the edges of said sections alongsaid guideways.

There is also an advantage in using metal for it will not warp out of shape thereby opening up cracks as in the case of wood, which will allow the air to enter. Furthermore, metalwill not buckle, break, stick, bind or freeze itself in set position.

Although the intention is not limited to any particular metal, the metal recommended and found to give good results is that of a heavy gauge carrying a large percentage of copper alloy and galvanize.

The door herein described can be applied in constructing new silos or to a silo already in operation whether it be made of Wood, tile, cement or metal of the round, square or octagon shape.

Moreover, by arching the door inward, there is provided more clearance between the surface 'of the rungs of the ladder and the surface. of the door, to insure greater footspace to the person climbing the ladder.

The object will be understood by referring to. the drawing in which,

Fig. 1 is an elevational view of a silo showing the novel door applied thereto, also a novel takeup device for the metallic bands that surround the silo.

Fig. 2 is a detail enlarged View showing a perspective of one of these sections of the, novel door.

Fig. 3 is a detail view showing an elevation, parts in fragment and parts being sectioned,- of two of the many sections of the novel door in closed position.

Fig. l is a detail enlarged view showing a perspective of the door frame and one of the secions of the door, parts being broken away and parts in section. v

Fig. 5 is a detail enlargedview showing a plan, parts being in section, of the take-up mechanism for the hoop or ring that encircles the silo.

Fig. 6 is a detail View showing the perspective of a modification employing a cleat attached to the frame member that might be used on silos already in service. 7

Fig. 7 is a detail view showing a step member that may be applied to the door opening.

Referring more particularly to the drawing, a silo of ordinary construction is represented by l; a vertical doorway 2 is made in th outer wall of the silo reaching from theground to the top thereof. This doorway is composed of frame side pieces 3, 3 made of wood or other suitable material across which are spaced at regular intervals metal spanners 5, 5 that may be used as a ladder, whereby the owner of the silo can ascend to the top thereof.

The door of the silo is made of a plurality of metal sections 10, 10. The metal most desirable is a heavy gauge galvanized metal carrying a large percentage of copper alloy. Each section 10 is arched or formed on a segment of a circle as shown particularly in Fig. 2. The upperportion of section 10 is bent inward the amount of thickness of the section, whereby to provide an offset portion 11 for the overlapping of the lower part 12 of the section 10 next above. The upper edge of section 10 is rolled or turned over as at 15'-to provide not only a handle but also to form asurface that will cause the edge of section next above to ride down and past without dilficulty Moreover, such a turned edge avoids a sharp corner that, might injure the workmen in takingthe ensilage'fromthe'silo. The lateral edges of'each section 10"is doubled back upon itself and bent inward towards each other making a re-entrant angle as" at'18, 18, whereby to provide flanges 17,17. Each of these bent in flanges or portions 1'7 form a 'V-shape member 19, that fits within a corresponding recess 21 madein each of the Woodenv door frames; side pieces 3, 3; It will be observed'that'the members 1'0," 10 form a close fit in theirrespective recesses 21, 21 in frame side pieces 3; 3 sufficiently tight to hold eachof thesections 10 in predetermined location and yet allow for sliding therein in an easy manner when pushed-upwards ordownwards by hand.

.Furthermore sections 10 will tend to remain in given or predetermined position due to pressure exerted from the inside by the ensilage'against the convex surface 23 o'f'each of sections 10. This pressure will be'resolved'in: two directions, one against the apex or edge 18 of the bent edge 17 and the otheragainst the faceiportion'25 of'lateral edgeTl-effecting a double contact at those locations. This double contactcaused by said pressure on the. inside convex'surface 23 of each of sections"10"will make a hermeticallytight or doubly sealed joint, whereby to prevent the admissionof air.

After the doorway 2 of the silo is constructed, sections '10 may be sprung into position;where by edges 17, 1'7 of each section 10 will occupy g'rooves-21*,"21 formed'in thedoor frame side pieces 3, 3. When sections 10 arain closed position they will slightly overlap at portions 11 .12:.. mac

-1When the user wishes to withdraw the ensilage from'the'silmhe removes the topmost'section 10 and thereafter pushes upwardv each next lower succeeding section 10 in grooves or recesses 21, 21 to uncover onespace at a time the length of a section 10, whereby to keep pace with the gradually loweringlevel of the ensilage; It'will be observed therefore, that as the ensilage is graduallyremoved and itslevel lowered, that each succeeding section'10'is slid upwardly with the exception of the'topmost section 10 which is removed thereby leaving an'opening equivalent to one-section at any given or predetermined time.

When refilling, sections 10 will be-lowered respectively'at regular intervals in reverse order to keep pace with the gradually rising level of the ensilage:

The invention also contemplates a take-up device'for adjusting the bands or rings with relation to the lateral wall of the silo. Furthermore, the take-up device allows for rings that do not interfere with the doorway or ladder.

In the present instance each of the bands or rings 40 are equipped with threaded ends as at 41, 41. These threaded ends are engaged in each instance by the internal threads of a hollow tubular member 42, that has a loose bearing in an aperture 43 formed in the rung or door spanner 44 of the ladder. Each of the hollow tubular members has an angular headed portion 45 for the application of a wrench. By turning tubular members 42 the rungs 44 can be adjusted with reference to their tightness about the silo 1.

It will be observed that rungs or door spanners 44 are arched outward to allow for holding tubular members 42, 42 at each end thereof. This arching outward of rungs 44 and inward of sections 10 of the door of silo 1 will allow for ample clearance or space between the outward surfaces of sections 10 and rungs 44 to insure a perfect foothold on said rungs44 when climbing the ladder.

' It will be observed that by using members 42, 42, bands or rings 44 canbe tightened or adjusted at the most convenient point; namely, the door opening and this without the bands or rings 44, 44 protruding into the door opening.

This door can be applied to a'silo already built and in use by nailing cleats 50, 50 to side pieces 3; 3 of the frame, whereby to form grooves 51, 51 corresponding to the grooves or recesses 21, 21 in 'side'pieces 3, 3 of the frame; or the grooves 51, 51 can be formed in the concrete when concreteis used in place of side pieces 3, 3' of the frame.

In Fig. 7 there is shown a member 60 which is used to protect the top or bent over edge 15 of each of sections 10, 10. When removing the ensilage the top edge 15 of each section 10 will be successively exposed and covered and protected by member 60. Member 60 is formed of wood preferably, and has grooves 61, 61 that fitthe corresponding edges of frame pieces 3, 3 of the door; As the ensilage is lowered and each section 10 is moved upward to accommodate the lowering of the ensilage in the silo, member 60" will be removed and placed on the edge 15 of the next lower section 10 thereby alwaysprotecting the upper edge 15 of each exposed section and making a perfectly safe footing should user step on top of door. Furthermore, member '60 is used to close the opening between the top section 10 and the roof 65 of the silo.

' Having thus described my invention what I claim as new and desire to secure by Letters Patent is as follows:

1. In a door for silos, a framework having guide grooves therein, a door having sections for slid ing in said guide grooves, said door having its edges doubled back upon itself and bent inward on a re-entrant angle to provide flanges, said door being arched inward, whereby its edges tend to spread under pressure from within said silo.

2. Ina door for silos, a member comprising metallic sections, guideways for mounting said sections, said sections having their edges bent inward on a re-entrant angle to form flanges, said door being arched inward, whereby its edges tend to-spread under pressure from within said silo.

3. In a door for silos, a member comprising sections, guideways for mounting said sections, said sections having their edges bent inward on a reentrant angle to form flanges and said door being arched inward, whereby its edges will tend to spread under pressure from within said silo.

4. In a door for silos, having an opening, a. member comprising a plurality of sections, guideways formed in said opening to allow for the sliding movement of said sections, said sections having their edges bent inward on a re-entrant angle to aid in holding them in position and said sections being arched inward, whereby to cause the pressure from within the silo to spread said edges to further aid in holding said sections in predetermined position.

5. In a door for silos, a member comprising a plurality of sections, guideways formed in said 

